Minerals A-L from the Lime Crest and Farber Quarries
ALBITE: "Popcorn rock" is the common name given to coarse-grained masses of albite at Lime Crest. I understand this to be a pseudomorph after calcite. Some albite from Lime Crest is also fluorescent under midrange UV. I have not found any well-formed albite crystals so far at the quarries, even in micro specimens. They exist, I'm sure.
ALLANITE: a "metamict" mineral, one that lacks definite internal structure due to radioactive breakdown over millenia. Brittle, prismatic or tabular allanite crystals occur in the pegmatite bodies at Lime Crest and at Franklin quarry. It is very difficult to isolate crystals of allanite from the matrix without breaking them, but you might get lucky and split the rock just the right way to preserve a 2 to 4mm crystal. Allanite is sometimes mildly radioactive.
ARAGONITE: chemically identical to calcite; different structure. Abundant as coatings on weathered rocks. Typically is mildly phosphorescent after exposure to UV light.
BARITE: found at Lime Crest; I'm not sure about the
other quarries in
the area, but I'd presume it would occur. One can find tabular, whitish
crystals at Lime Crest. Sometimes they are distorted or saddle-shaped,
but
simple tests show they are barite. This mineral also appears in several
other
forms: dense, layered, granular, etc.
I have a few small specimens of bladed barite I've picked up in Lime
Crest.
CALCITE: Calcium carbonate. At Lime Crest there occur
some clear,
short, pseudo-hexagonal calcite prisms, sometimes found with small
pyrite
cubes. Such perfect calcite crystals are uncommon, but worth looking
for.
Attractive micromounts and thumbnail specimens, these. They also
fluoresce
yellow-orange to whitish under longwave. Calcite as a species is
extremely common at the quarries, considering most of the marble
consists of it.
CHLORITE (CLINOCHLORE): a micaceous mineral which occurs as tiny aggregates of greenish, yellowish-green, or brown plates. They appear hexagonal (like mica) but are actually monoclinic. This mineral occurs in the area quarries.
CORUNDUM: found as gray, blue-gray, and rarely blue (sapphire) varieties in Lime Crest and Franklin quarries. Crystals are most often anhedral or subhedral, subtranslucent to nearly opaque. Corundum also occurs in massive form. There is always the possibility, though, that one can find a distinctly-formed corundum crystal here.
EDENITE: pale green amphibole found in calcite.
Practically
impossible for the beginner to distinguish from actinolite or the other
amphiboles without some
sophisticated tests, although I have more than one amphibole specimen
from Lime
Crest which I'm pretty sure is edenite, based on showing it to sight-ID
people possessing a great deal more experience than I have.
FERROAXINITE: This mineral occurs in Lime Crest, and
has also been
found in one or two places in Warren County. A few specimens from the
Oxford Quarry are floating around on the mineral market today.
Once in a while you might find
small, "ax" or wedge-shaped crystals of it.
FLUOBORITE: I think it was the old Edison Quarry where good fluorescent specimens of this mineral were from; however, it occurs in smaller amounts at Lime Crest and probably Farber. We did find a small amount of fluorescent fluoborite in Lime Crest. Fluoborite occurs in the marble from Ogdensburg, NJ clear up through Orange County, NY and probably up into Canada, yet I wouldn't consider it all that common... not in good (fluorescent) specimens, at least.
GARNET: a reddish variety appears in the Lime Crest quarry, associated with the midrange-fluorescing albite and microcline. It is usually in massive form, but is still very attractive because of its color. Occasionally there turns up a crystal of this garnet, but these are usually subhedral and nearly opaque.
GRAPHITE: many peculiar forms of graphite occur as micro-specimens at the area quarries. The most sought-after form is the "radiating graphite", a fragile specimen of graphite "fins" that radiate out from a central point. These are usually about 7 or 8 millimeters across. Several collectors have found "radiating" graphites at Lime Crest. Plates of graphite are easy to confuse with molybdenite.
HEMIMORPHITE: has been found at area quarries. Would probably be near sphalerite or some other zinc-bearing region in the metamorphosed limestones. Botryoidal crusts of white, gray or tan minerals can also be aragonite. When they're in this form, the minerals can be easily confused without some simple chemical tests.
HORNBLENDE: Monoclinic crystals, usually prismatic,
occur at Lime
Crest and probably the other quarries of the area. Hornblende can also
be
massive form. Usually it's black, but can also be dark green or (I
think)
brown. The green varieties can be confused with other amphiboles such
as
edenite. I don't think "hornblende" is an IMA-approved species of
its own, but FERROHORNBLENDE
certainly is.
HYDROZINCITE: since this is formed as an alteration product of sphalerite, you'd expect to find it near that mineral. Most of the hydrozincite, therefore, came from the Lime Crest MVT deposit, which had abundant sphalerite.
ILMENITE or HEMATITE
crystals have been found in Lime Crest, together with a grayish variety
of CORUNDUM and a silvery-gray, micaceous mineral that may be MARGARITE. The ilmenite (or hematite) crystals are metallic, dark steel-gray. Since I don't have access to Goldschmidt's Atlas der Krystallformen at the moment, I haven't been able to match the particular crystals to one or the other species.
LOELLINGITE: (Hardness: 5 to 5.5; Streak:
black; Gravity: 7.1 to 7.5; Other: dissolves in nitric
acid to leave
yellow solution)
Iron
di-arsenide, easily
confused with (and often accompanied by) the iron-arsenic sulfide ARSENOPYRITE
(Hardness: 5.5 to 6; Streak:
black; Gravity: 5.9 to 6.2; Other: gives positive
sulfur
test).
Both these
minerals have
a silvery color & metallic appearance; however, loellingite is of
the
orthorhombic system, while arsenopyrite is monoclinic.
Loellingite
occurs
usually as blebs or grains in limestone and in the contact zones. It's
associated with arsenopyrite, graphite, norbergite, titanite, pyrite,
pyrrhotite, dravite, and / or a silvery mica (muscovite?). I found one
tiny
crystal at Lime Crest with the right appearance and shape to be
loellingite.
Fine loellingite
or
arsenopyrite particles are non-magnetic (unlike those of pyrrhotite).
Loellingite and arsenopyrite also give off a garlic (arsenic) smell
when
freshly broken, and fresh surfaces lack the weak bronze hue of
pyrrhotite.
